Sound reproducing apparatus



Dec. 29, 1931. c. HEISLER V SOUND REPRODUCING APPARATUS Filed Sept. 25, 1929 2 Sheets-Sheet Inventor- ChcmLes L. HeLsLer, b 5? 7m HLS Attor'ne Dec. 29, 1931. c. L. HEISLER SOUND REPRODUCING APPARATUS Filed Sept. 25, 1929 2 Sheets-Sheet Inventor ChcmLes L. HGLSLGT',

IILs Attorme I PatentedD ec. 29, 1931 UNITED. STATE PATENT OFFICE I CHARLES L. HEISLER, OF SOHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELIG- TRIO COMPANY, A CORPORATION OF NEW YORK SOUNIJ REPRODUGING APPARATUS Application filed September 25, 1929. Serial- No. 395,169.

My invention relates to apparatus bly which sound may be reproduced electrical y from a photographic sound record on a film of the motion picture type, and the object of my invention is the provision of improved supporting means for the film and for the photoelectric member associated therewith.

My invention will be better understood from the following description taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims. This application is a continuation in part of my co-pending application Serial No.- 203,344, filed July 5, 1927, now Patent No. 1,771,922, July 29, 1930.

Referring to the drawlngs, Fig. 1 is a side elevationpartly in section of a portion of a reproducing apparatus involving my invention; Fig. 2 is a plan view of the same also partly in section; Figs. 3 and 4 are detail sectional views taken respectively on the lines 3-3 and 4 -4 of Fig; 1; and Fig. 5 is a disassembled view of the photo-electric cell supporting means.

In he drawings, the frame 1 of the reproducing machine forms a bearing forthe shaft 2 which beyond the bearing carries the film supporting drum 3. The drum, which is preferably constructed of steel, is hollow and is divided circumferentially to form a two-part structure, one part or member 4 being fixed to the shaft and the other'part or member 5 being detachably secured to'the outer or free end of the shaft. The film 7, of the motion picture type, in its passage from the take-01f reel to the take-up reel, both not shown, passes from the guide roller 8 over drum 3 to the pressure roller 9. To insure a more uniform rotation of the drum, the shaft 2 preferably has a fly-wlieel mounted thereon. Either the drum may be driven at the desired speed by 1 a connection through the shaft 2 with suitable driving apparatu's, such as an electric motor, ,or thedrum and fly-wheel may be driven partly or solely by the pull of the film.

rubber tire 10' which is let into the face of the drum so that its periphery is flush with the drum surface. A light beam from a suitable source, not shown, is focused by an optical system shown in part at 12 on the sound record in the form of a very narrow beam which after passing through the record enters the photo-electric cell 13. By this construction the film is firmly supported on both sides of and immediately next to the sound track, thus insuring that the sound record on the film shall remain at all times in the proper focus of the optical system.

'Access to the photo-cell 13 is obtained by the removal of the drum portion 5 from the shaft 2. The end portion of the shaft is tapered at 15 and the boss 16 on the drum portion 5 is correspondingly tapered. Thumb nut 17 threaded on the end of shaft 2 clamps the tapered portions together.

The drum not only supports the film in proper focal position at the point of li ht interception, and by reason of the .attac ed fly-wheel insures a high degree of uniformity of motion thereof, but also shields the photocell from various electrical disturbances which otherwise produce objectionable noises in the reproduced sound.

Attached to the frame 1 is the support 20, a portion 21 of which is shown extending through the opening 22 of. frame 1 and termina'ting in the contact housing 23. Detachably secured to this housing by the thumb nut'24 is the bracket 25 preferably of steel, which extends through the space between the two drum portions and has attached to it the insulation block 26. This block surrounds the shaft 2 with sufiicient clearance to avoid actual contact, and at one side has the recess 27 for receiving the photo-cell 13, suitable socket contacts being provided in the block for engagin the contact posts on the end of the cell. gne of the connecting wires is shown embedded in the groove 28 in the bracket and the other is shown enclosed in the steel tube 29 on the side of the bracket. These wires terminate in the plugs 30 in the insulation block 31, and are received by socket contacts in the insulation block 32. From these socket contacts, connecting wires 33 extend into the steel transformer housing 34 from which suitable connection is made to amplifying apparatus and loud speaker or a free end portion, a drum on said portion adapted to sup ort a record film, said drum comprising a p ura-lity of separate cylindrical members spaced apart axially and separately mounte on said portion, a photo-electric cell mounted within the drum and means for detachably securing the outermost member to the shaft.

2. In apparatus for reproducing sound from a film record, a rotatable shaft having a free end portion, .a drum on said portion adapted to sup ort a record film, said drum comprising a p urality of separate cylindrical members spaced apart axially, one of said members being fixed to the shaft, the other of said members and the shaft being tapered and means for clamping together the shaft and said other member.

3. Inapparatus for producing sound from a film record, a rotatably mounted shaft having a free end portion, a film sup orting drum on said portion comprising a p urality of separate axially spaced members, the outermost of said members .being detachably sew cured to the shaft independently of the other member, a photo-electric cell between the shaft and the eripheral wall of the drum, a bracket exten ing between the drum members for supporting the, cell, a support for the bracket, means for detachably connecting the bracket to the support, a conductor carried by the bracket and coo erating detachable circuit connectors on the racket and the sup- 4. In apparatus for reproducing sound 

